Hi there!
First of all, I believe if you are really new to RPG Maker in general, you shouldn't be looking for plugins at all. Learn the engine first, and make a project without plugins to learn how to use the engine.
Now, this plugin does not remove any parameters from classes. It just adds new ones. And these new ones are not shown on the menu.
What can you do, with the default RPG Maker, is go into the Database/Terms and change the name of some parameters to "fake" them. Like, let's say you want to remove the Luck parameter and add a Rage parameter. Just rename Luck to Rage.
That can work for you?